Separate loading ammunition ramming assist



Feb. 4, 1964 H. s. LIPINSKI SEPARATE LOADING AMMUNITION RAMMING ASSIST Filed May 25, 1962 0341 025040 QZ ww o W E EW Q m W IL 0 sM /n Y m d E/W z Uite States The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

In anti-tank weapons using separate loading ammunition a spiked nose projectile has been used without the usual ogive, which ogive has heretofore assisted in guiding and seating the projectile into its proper firing position. Because of the spiked nose, there has been a tendency to have the projectile seated in a canted position with its axis not in coincidence with longitudinal axis of the gun. Difficulty in seating the projectile correctly is due perhaps to two causes. One was the absence of the usual ogive and a more serious cause was the fact that the projectile in being moved forward along the tapered chamber for the cartridge case had its axis out of alinement with the gun axis resulting in the projectile being too often incorrectly canted by being jammed before reaching its proper position in its chamber for being fired.

An object of this invention is to insure correct seating of the projectile in such guns in their firing chambers, whereby the gas seal and the resulting accuracy in use of the guns is enhanced.

Specifically a rounded protusion is provided on the rear axial end portion of the projectile with its rear edge rounded. The projectile is not rammed home in one step because of the tendency for such to be incorrectly and prematurely seated due to the incline or tapered shape necessary for the propellant chamber. Instead it has been found desirable to end its initial movement Well short of a position with its rotating band or a jacket ready to engage the lands and grooves. The propellant in a cartridge case is fed in behind the projectile but its forward end is provided with a front end wall closing plug having a tapered mouth in which said protusion is received. Pushing both the cartridge case and projectile causes the rear end of said projectile to be raised as the protrusion moves up the incline in said plug. This causes the projectile to be more nearly accurately seated.

Referring to the drawing:

FIG. 1 is a longitudinal View showing the outline of a generally prior projectile and separately loaded propellant case except for front end wall of the case being shown partly in section,

FIG. 2 is a detail showing a projectile in a canted position ready to have its rear end raised by the case front end wall,

FIG. 3 is an elevation view of the nose portion of the projectile.

Except for the protrusion ill on the rear end of a projectile 11.1, and a front wall 12 on a propellant case 13, projectile and case are old as are the tapered chambers lid for receiving a rear portion of the projectile and 15 for receiving said tapered case 13.

The projectile it is of the fin stabilized type having a low speed of rotation of it) to revolutions per second preferably induced by rifting 17 in a gun barrel beginning at about the place 18 where the lands and grooves begin to cut into a rotating band 19, or its equivalent. A spiked nose 2% of the projectile prevents the usual ogive being present to assist in guiding the projectile into its firing position better than can this nose 20. A usual boom 21 has stabilizing fins 22 on its rear end.

The case 13 contains the usual propellant 23 and is of the tapered shape shown. A primer cup 24 is located in the rear end of the case 23 for being fired in a usual manner. A base flange 25 forms a groove 26 in which an extractor engages to pull out the case after being fired. The case being of soft metal and as large a size as for a mm. projectile expands into tight contact with the chamber walls on being fired. These chamber walls have been tapered to facilitate extraction and a shoulder 27 is formed to limit inward movement of the case.

Heretofore it has been customary to push the projectile home in one movement but this was found unsatisfactory because of a tendency for it to get stuck in a canted position due to the absence of any guiding ogive before reaching its proper position and due to the projectile being pushed up a ramp formed by the longitudinally tapered walls of chambers 14 and 15. The spike type nose seemed to be a contributing cause of the projectile getting stuck in some inclined position. The prior art projectile and propellant case have not provided any solu tion to this difficulty. Without the projectile being properly seated in its intended position for firing there was an objectionable error in velocity and range for the projectile due to improper sealing of the gases.

Now the projectile has been provided with an improvement eliminating these disadvantages. One view of this invention has contemplated the projectile being moved home in two steps instead of one. In the first step the projectile is moved up the ramp constituted by the bottom 223 of the tapered surface 15 on which the projectile and case must be moved, from the breech end of the gun. In the next step the projectile is moved home by the case pushing it forward from its first position and in doing so simultaneously raising the rear end of the projectile into or more nearly into alignment with the longitudinal axis of the gun.

Such is accomplished by providing a protrusion 19 of lig tmetal such as aluminum of cup shape and thick enough to stand the force necessary for the lifting and pushing without its being deformed in the process. This protrusion is secured to the boom 21 or fins 22 in any convenient manner such as by means of a pin threaded into the boom interior or into the hub of the fin casting. This protrusion ltl is of aluminum approximately one inch long with its rear edge rounded about as illustrated so that there will be no sharp edge likely to cut into the material of the front wall 12 of the case closure.

The front wall 12 of the case 113 is of the general shape illustrated and is preferably of a material which is consumable or frangible or one such as a plastic having a smooth surface offering little frictional resistance to the protrusion 10 riding up a tapered wall 2d of the recess 3% in the plug or front wall 12. One such plastic is an inexpensive one composed of abestos and asphalt with a wood filler known commercially as Besphalt. Another and preferred one is a phenolic plastic CF 1-20 of specification MlLM-14. This plastic material is not critical. The Tefion plastic would be admirable but for cost. Many others could be used. The rim of the closure plug 12 is shouldered to receive the forward edge of the propellant case 13. The joint between plug 12 and case 13 is preferably made moisture proof in ways familiar to the art.

Among the advantages of this invention may be mentioned the elimination of the wasted time of a gunner striving to aline the projectile when some forward portion of it gets caught in the forcing cone 18 where the rifling begins. It is now possible to load the case and have the case front Wall 12 and recess 30 automatically raise the rear end of the projectile so that the previously loaded projectile will be correctly moved into its position for firing. By performing the projectile loading or ramming forward operation in the two steps described instead of one the projectile is thus assured of being brought into horizontal alinement Without diificulty.

I claim:

1. In separate loading fin stabilized round of ammunition comprising a tapered metal case containing propellant, and a projectile for loading in a gun in which a chamber for receiving said case is also tapered to approximately the taper of said case to facilitate extraction and at least a portion of the projectile receiving chamber is substantially similarly tapered, said projectile having a spike nose and a tendency to be axially tilted with respect to a gun axis when not pushed into its home position, the combination therewith of the improvement enabling said propellant case to assist in more nearly alining said projectile with a gun axis, said improvement including an axial protrusion on a rear end of said projectile, said protrusion being of less diameter than said projectile, said case having a front wall closing said case and provided with an axial recess tapered longitudinally and radially outward and of a size to receive said protrusion in any position of said projectile as said case is pushed forward up the bottom side portion of its tapered chamber, whereby a bottom of said recess may receive said protrusion and raise a rear portion of said projectile as said case is moved forward.

2. A combination according to claim 1 in which the mouth of said wall recess is of a diameter which is about half that of said wall and about double that of said protrusion, the outward taper to the walls of said recess being about 45 to facilitate raising a rear end of said projectile as said case is pushed forward in its chamber into position for firing the propellant, and of a depth at least about the axial length of said protrusion.

3. A combination according to claim 2 in which the front Wall closing said case is at least one of comsumable and frangible materials and said protrusion is of aluminum.

4. A combination according to claim 2 in which an outer edge portion of said protrusion is rounded to facilitate it sliding up an inclined recess wall.

5. In separate loading fin stabilized ammunition comprising a metal case, a propellant in said case, means whereby said propellant may be ignited, the combination therewith for better aligning a projectile in front of said case and separate therefrom when said projectile has a rearward axial protrusion, said improvement including the forward portion of said case having a front wall sealing said propellant and said front wall having a tapered axial recess of a size to receive said protrusion and an inclination to said tapered recess of about 4 to the case axis and capable of raising said protrusion into approximate alignment with said case on moving said case forward to position the same with a base flange contiguous a gun breech opening.

6. A propellant case according to claim 5 in which said front wall is of one of a consumable material and a frangible material.

References Cited in the file of this patent UNITED STATES PATENTS 225,464 Coloney Mar. 16, 1880 1,209,611 Mustin Dec. 19, 1916 2,389,846 Ericson Nov. 27, 1945 2,811,901 Barr NOV. 5, 1957 2,820,412 Beeuwlces et al Jan. 21, 1958 2,982,212 Robinson May 2, 1961 3,011,407 Koningsveld Dec. 5, 1961 3,055,268 Rosenthal Sept. 25, 1962 

1. IN SEPARATE LOADING FIN STABILIZED ROUND OF AMMUNITION COMPRISING A TAPERED METAL CASE CONTAINING PROPELLANT, AND A PROJECTILE FOR LOADING IN A GUN IN WHICH A CHAMBER FOR RECEIVING SAID CASE IS ALSO TAPERED TO APPROXIMATELY THE TAPER OF SAID CASE TO FACILITATE EXTRACTION AND AT LEAST A PORTION OF THE PROJECTILE RECEIVING CHAMBER IS SUBSTANTIALLY SIMILARLY TAPERED, SAID PROJECTILE HAVING A SPIKE NOSE AND A TENDENCY TO BE AXIALLY TILTED WITH RESPECT TO A GUN AXIS WHEN NOT PUSHED INTO ITS HOME POSITION, THE COMBINATION THEREWITH OF THE IMPROVEMENT ENABLING SAID PROPELLANT CASE TO ASSIST IN MORE NEARLY ALINING SAID PROJECTILE WITH A GUN AXIS, SAID IMPROVEMENT INCLUDING AN AXIAL PROTRUSION ON A REAR END OF SAID PROJECTILE, SAID PROTRUSION BEING OF LESS DIAMETER THAN SAID PROJECTILE, SAID CASE HAVING A FRONT WALL CLOSING SAID CASE AND PROVIDED WITH AN AXIAL RECESS TAPERED LONGITUDINALLY AND RADIALLY OUTWARD AND OF A SIZE TO RECEIVE SAID PROTRUSION IN ANY POSITION OF SAID PROJECTILE AS SAID CASE IS PUSHED FORWARD UP THE BOTTOM SIDE PORTION OF ITS TAPERED CHAMBER, WHEREBY A BOTTOM OF SAID RECESS MAY RECEIVE SAID PROTRUSION AND RAISE A REAR PORTION OF SAID PROJECTILE AS SAID CASE IS MOVED FORWARD. 